Insertion device

ABSTRACT

A device includes: a first magnet array; a first magnet support body; a second magnet array; a second magnet support body; a gap drive mechanism for performing vertical drive of the magnet support bodies to change a gap; first, second connection beams connected to the magnet support bodies; a mechanism for connecting the connection beams to the gap drive mechanism; a cancellation spring mechanism for cancelling a suction force that acts between magnet arrays; and a spring interlocking mechanism for connecting the cancellation spring mechanism to the magnet support bodies. In the spring interlocking mechanism, first and second spring support frames that are connected to the first and second connection beams via a connecting portion, and a guide mechanism for guiding vertical movements of the first and second spring support frames are mounted, and the cancellation spring mechanism are mounted to both the first and second spring support frames.

TECHNICAL FIELD

The present invention relates to insertion devices including a firstmagnet array constituted by a plurality of magnets placed in an array, afirst magnet supporting member for supporting the first magnet arraymounted thereto, a second magnet array which is constituted by aplurality of magnets placed in an array and is faced to the first magnetarray with a gap interposed therebetween, a second magnet supportingmember for supporting the second magnet array mounted thereto, a gapdriving mechanism for driving the first magnet supporting member and/orthe second magnet supporting member in the direction in which the magnetarrays are faced to each other, in order to change the size of the gap,and a driving conjunction mechanism for coupling the gap drivingmechanism and the magnet supporting members to each other.

BACKGROUND ART

If an electron beam having been accelerated to near the light velocityin a vacuum is bent within a magnet field, radiated light is emitted intangential directions of the trajectory of the movement of the electronbeam. This is called synchrotron radiation. There have been made studiesfor practical applications of various techniques for installing lightsources for generating such synchrotron radiation in straight sectionsof electron storage rings (electron-beam accumulating rings), in orderto utilize its properties such as high directivity, high intensity, andhigh polarization properties. Existing electron storage rings have beenprovided with plural insertion devices (undulators), as high-brightnesslight sources with higher beam electric currents and smaller beamcross-sectional areas.

As such insertion devices, there has been known an insertion devicedisclosed in the following Non-Patent Document 1, for example. Thisinsertion device has a structure including a first magnet arrayconstituted by a plurality of magnets placed in an array, and a secondmagnet array constituted by a plurality of magnets placed in an array,which are faced to each other with a gap interposed therebetween. Sincethe arrays of the plural magnets are faced to each other, largeattractive forces are exerted between both of them. Due to the exertionof the attractive forces, large loads are induced in gap drivingmechanisms, which causes degradation of precise gap driving anddeformations of magnet supporting members supporting the magnet arrays,thereby disordering the magnetic-field intensity distribution in thedirection of an electron beam, which has been initially set in themagnetic-field generating space (the gap). This has resulted in theproblem of impossibility of generation of synchrotron radiation withdesired properties.

The following Patent Document 1 discloses a structure provided withcompensation springs, in order to overcome the aforementioned problem.In this insertion device, girders for supporting magnet arrays aredriven in vertically upward and downward directions, through gap drivingmechanisms provided on a primary frame configuration (primary frame).This gap driving mechanisms are for changing the size of a gap. Further,the girders for supporting the magnet arrays are supported by secondaryC-frame configurations (secondary C-frames) with spring assembliesinterposed therebetween. The secondary C-frame configurations arecoupled to both the left and right sides of the primary frameconfiguration. These spring assemblies are intended to reduce the loadsexerted on the gap driving mechanisms, and also to suppress thedeformation of the girders as the magnet supporting members.

PRIOR ART DOCUMENTS Patent Documents

Patent Document 1: U.S. Pat. No. 7,956,557 B1

Non-Patent Document 1: Winick, Herman; George Brown; Klaus Halbach; JohnHarris (May 1981). “Synchrotron Radiation Wiggler and Undulator Magnets”Physics Today, May 1981, Volume 34, Issue 5, pp. 50-63

SUMMARY OF THE INVENTION Problems to be Solved by the Invention

However, the structure disclosed in Patent Document 1 has problems asfollows. Namely, the gap driving mechanisms mounted on the primaryC-frame configuration are configured to be directly coupled to thecompensation spring mechanisms with the secondary C-frame configurationsinterposed therebetween. Therefore, moments induced by the compensationspring mechanisms may cause deformations of the gap driving mechanisms,and the deformations of the gap driving mechanisms may degrade theprecise gap control. Accordingly, even though there are provided thecompensation springs, their performance has not been exertedsufficiently. Further, the compensation springs are placed just aboveand just under the girders which support the magnet arrays and,furthermore, the secondary C-frame configurations are provided justabove and just under these compensation springs. This structure also hasthe problem of increases in size in the upward and downward directions.

The present invention has been made in view of the aforementionedcircumstance and aims at providing an insertion device capable ofpreventing moments induced by compensation spring mechanisms frominfluencing precise gap driving and also capable of inhibiting theincrease in size of the device.

Means for Solving the Problems

In order to solve the above problem, an insertion device according tothe present invention comprising:

a first magnet array comprising a plurality of magnets placed in anarray;

a first magnet supporting member adapted to support the first magnetarray mounted to the first magnet supporting member;

a second magnet array comprising a plurality of magnets placed in anarray and being faced to the first magnet array with a gap interposedtherebetween;

a second magnet supporting member adapted to support the second magnetarray mounted to the second magnet supporting member;

a gap driving mechanism for driving the first magnet supporting memberand/or the second magnet supporting member in a direction in which themagnet arrays are faced to each other, in order to change a size of thegap;

a first coupling beam coupled integrally to the first magnet supportingmember;

a second coupling beam coupled integrally to the second magnetsupporting member;

a driving conjunction mechanism for coupling at least one of the firstcoupling beam and the second coupling beam to the gap driving mechanism;

a compensation spring mechanism adapted to act in such a direction as tocancel an attractive force acting between the first magnet array and thesecond magnet array; and

a spring conjunction mechanism for coupling the compensation springmechanism and the coupling beams to each other,

wherein

the spring conjunction mechanism includes:

-   -   a first spring supporting frame coupled, through a first        coupling portion, to one of the first coupling beam and the        second coupling beam,    -   a second spring supporting frame coupled, through a second        coupling portion, to the other one of the first coupling beam        and the second coupling beam, and    -   a guide mechanism for guiding relative movement of the first        spring supporting frame and the second spring supporting frame,        in the direction in which the magnet arrays are faced to each        other,

the compensation spring mechanism is mounted to both the first springsupporting frame and the second spring supporting frame and, when thesize of the gap is changed, the first spring supporting frame and thesecond spring supporting frame move relative to each other in thedirection in which the magnet arrays are faced to each other, so thatthe compensation spring mechanism operates.

With the insertion device having the aforementioned structure, it ispossible to provide effects and advantages as follows. The first magnetsupporting member is integrally coupled to the first coupling beam, andthe second magnet supporting member is integrally coupled to the secondcoupling beam. The gap driving mechanism drives at least one of thefirst coupling beam and the second coupling beam for changing the sizeof the gap. On the other hand, the spring conjunction mechanism includesthe first spring supporting frame and the second spring supportingframe, which are coupled to one and the other one of the first couplingbeam and the second coupling beam, through the first coupling portionand the second coupling portion, respectively. Further, the first springsupporting frame and the second spring supporting frame are allowed tomove relative to each other, through the guide mechanism, in thedirection in which the magnet arrays are faced to each other. With thisstructure, moments induced by the operations of the compensation springmechanism can be received by the guide mechanism, which inhibits suchmoments from influencing the gap driving mechanism through the first andsecond coupling portions. This can prevent the operations of thecompensation spring from influencing the precise gap driving.

Further, the direction in which the magnet arrays are faced to eachother depends on the state where the magnet arrays are installed. Thedirection in which the magnet arrays are faced to each other includesthe vertical direction, the horizontal direction and arbitrary obliquedirections, for example. Further, movements in the direction in whichthe magnet arrays are faced to each other include both cases where themagnet arrays get closer to each other and cases where the magnet arraysget farther away from each other.

Further, “the compensation spring mechanism is mounted to both the firstspring supporting frame and the second spring supporting frame” meansthat the compensation spring mechanism is mounted at a portion thereofto the first spring supporting frame and, further, the compensationspring mechanism is mounted at another portion thereof to the secondspring supporting frame.

In the present invention, preferably, one of the first spring supportingframe and the second spring supporting frame includes a pair of firstplate portions, and a plate coupling portion which is provided on thefirst plate portions in their sides farther from the magnet arrays andis adapted to couple the first plate portions to each other, in a planview,

the first plate portions are coupled, at their sides closer to themagnet arrays, to one of the first coupling beam and the second couplingbeam, through the first coupling portion,

the other one of the first spring supporting frame and the second springsupporting frame includes a second plate portion placed in such a way asto be sandwiched between the pair of the plate portions in a plan view,

the second plate portion is coupled, at its side closer to the magnetarrays, to the other one of the first coupling beam and the secondcoupling beam, through the second coupling portion, and

the guide mechanism is provided between the plate coupling portion and aside of the second plate portion which is farther from the magnetarrays.

With this structure, the pair of the first plate portions and the platecoupling portion form a portal shape in a plan view (a top view), andthe second plate portion is placed in such a way as to be sandwichedbetween the pair of the first plate portions. Namely, the plate portionshave a three-layer configuration. The guide mechanism is providedbetween the plate coupling portion and the second plate portion in theside farther from the magnet arrays. Accordingly, even though thecompensation spring mechanism makes an attempt to exert moments on thefirst and second coupling portions, these moments can be absorbed by theguide mechanism, which can inhibit the moments induced by thecompensation spring from being exerted on the first and second couplingportions. This can prevent the operations of the compensation springfrom influencing the precise gap driving, more effectively.

In the present invention, preferably, one of the first spring supportingframe and the second spring supporting frame includes a pair of firstplate portions, and a plate coupling portion which is provided on thefirst plate portions in their sides farther from the magnet arrays andis adapted to couple the first plate portions to each other, in a planview,

the first plate portions are coupled, at their sides closer to themagnet arrays, to one of the first coupling beam and the second couplingbeam, through the first coupling portion,

the other one of the first spring supporting frame and the second springsupporting frame includes a second plate portion placed in such a way asto be sandwiched between the pair of the plate portions in a plan view,

the second plate portion is coupled, at its side closer to the magnetarrays, to the other one of the first coupling beam and the secondcoupling beam, through the second coupling portion, and

the guide mechanism is provided between the sides of the first plateportions which are farther from the magnet arrays, and a side of thesecond plate portion which is farther from the magnet arrays.

With this structure, the guide mechanism is provided between the sidesof the first plate portions which are farther from the magnet arrays,and the side of the second plate portion which is farther from themagnet arrays. Accordingly, even though the compensation springmechanism makes an attempt to exert moments on the first and secondcoupling portions, these moments can be absorbed by the guide mechanism,which can inhibit the moments induced by the compensation spring frombeing exerted on the first and second coupling portions.

In the present invention, preferably, one of the first spring supportingframe and the second spring supporting frame includes a first plateportion in a plan view,

the first plate portions is coupled, at its side closer to the magnetarrays, to one of the first coupling beam and the second coupling beam,through the first coupling portion,

the other one of the first spring supporting frame and the second springsupporting frame includes a second plate portion placed in such a way asto be faced to the first plate portion in a plan view,

the second plate portion is coupled, at its side closer to the magnetarrays, to the other one of the first coupling beam and the secondcoupling beam, through the second coupling portion, and

the guide mechanism is provided between a surface of the first plateportion in its side farther from the magnet arrays and a surface of thesecond plate portion in its side farther from the magnet arrays whichare faced to each other.

With this structure, the first plate portion and the second plateportion are placed in such a way as to be faced to each other. Namely,the plate portions have a two-layer configuration. The guide mechanismis provided between the first plate portion and the second plate portionin the side farther from the magnet arrays. Accordingly, even though thecompensation spring mechanism makes an attempt to exert moments on thefirst and second coupling portions, these moments can be absorbed by theguide mechanism, which can inhibit the moments induced by thecompensation spring from being exerted on the first and second couplingportions.

Preferably, the first coupling portion and the second coupling portionaccording to the present invention have a structure for coupling througha combination of a shaft and a fitting hole fittable to the shaft.

Due to the combination of the shaft and the fitting hole, even ifmoments induced by the compensation spring are exerted on the first andsecond coupling portions, the shaft and the fitting hole are allowed torotate relative to each other, which can inhibit the moments induced bythe compensation spring from influencing the gap driving.

In the present invention, preferably, one of the first spring supportingframe and the second spring supporting frame is provided with aplacement portion adapted to place, thereon, a compensation spring inthe compensation spring mechanism, and

the other one of the first spring supporting frame and the second springsupporting frame is provided with a compressive-force exertion portionadapted to exert a compressive force on the compensation spring.

With this structure, the spring force of the compensation spring can bechanged, through relative movement of the compressive-force exertionportion. Further, the compensation spring mechanism can be properlyplaced.

Preferably, the spring conjunction mechanism according to the presentinvention further comprises a fixed frame secured to a foundation, and aplurality of the guide mechanisms, and

the spring conjunction mechanism comprises:

-   -   a first guide mechanism adapted to guide the first spring        supporting frame relative to the fixed frame in the direction in        which the magnet arrays are faced to each other, and    -   a second guide mechanism adapted to guide the second spring        supporting frame relative to the fixed frame in the direction in        which the magnet arrays are faced to each other, and

when the size of the gap is changed, the spring conjunction mechanism isadapted to allow the first spring supporting frame and the second springsupporting frame to move relative to the fixed frame, in the directionin which the magnet arrays are faced to each other.

The first spring supporting frame and the second spring supporting framecan be adapted to move relative to each other in the direction in whichthe magnet arrays are faced to each other, and the fixed frame securedto the foundation can be provided, such that the first spring supportingframe and the second spring supporting frame can be each moved withrespect to the fixed frame. With this structure, it is possible tomaintain the spring conjunction mechanism at a stabilized state, due tothe provision of the fixed frame.

In the present invention, preferably, the second coupling portion isprovided on the first coupling beam in its side closer to the firstmagnet array, and the first coupling portion is provided on the secondcoupling beam in its side closer to the second magnet array.

Since the first coupling portion and the second coupling portion areplaced in the side as close as possible to the magnet arrays, it ispossible to inhibit the increase of the size of the spring conjunctionmechanism in the upward and downward direction, which can alsocontribute to weight reduction.

In the present invention, preferably, the spring conjunction mechanismis placed in the rear side with respect to the magnet arrays, in a sideview. This enables accessing the magnet arrays from the front side whenviewed from the front surface side. Further, this prevents the existenceof the spring conjunction mechanism from obstructing maintenances andthe like.

A compensation module for use in an insertion device, the insertiondevice comprising:

a first magnet array comprising a plurality of magnets placed in anarray;

a first magnet supporting member adapted to support the first magnetarray mounted to the first magnet supporting member;

a second magnet array comprising a plurality of magnets placed in anarray and being faced to the first magnet array with a gap interposedtherebetween;

a second magnet supporting member adapted to support the second magnetarray mounted to the second magnet supporting member;

a gap driving mechanism for driving the first magnet supporting memberand/or the second magnet supporting member in a direction in which themagnet arrays are faced to each other, in order to change a size of thegap;

a first coupling beam coupled integrally to the first magnet supportingmember;

a second coupling beam coupled integrally to the second magnetsupporting member; and

a driving conjunction mechanism for coupling at least one of the firstcoupling beam and the second coupling beam to the gap driving mechanism,

the compensation module comprising:

a compensation spring mechanism adapted to act in such a direction as tocancel an attractive force acting between the first magnet array and thesecond magnet array; and

a spring conjunction mechanism for coupling the compensation springmechanism and the coupling beams to each other,

wherein

the spring conjunction mechanism includes:

-   -   a first spring supporting frame coupled, through a first        coupling portion, to one of the first coupling beam and the        second coupling beam,    -   a second spring supporting frame coupled, through a second        coupling portion, to the other one of the first coupling beam        and the second coupling beam, and    -   a guide mechanism for guiding relative movement of the first        spring supporting frame and the second spring supporting frame,        in the direction in which the magnet arrays are faced to each        other, and

the compensation spring mechanism is mounted to both the first springsupporting frame and the second spring supporting frame and, when thesize of the gap is changed, the first spring supporting frame and thesecond spring supporting frame move relative to each other in thedirection in which the magnet arrays are faced to each other, so thatthe compensation spring mechanism operates.

The compensation module according to the present invention can beapplied not only to the insertion device according to the presentinvention, but also to various types of insertion devices which havebeen conventionally well known, particularly to insertion devicesadapted to exert large attractive forces between magnet arrays, therebycausing the exertion of these attractive forces to adversely influenceprecise gap driving and magnetic-field intensity distributions in thedirection of an electron beam. By applying the compensation moduleaccording to the present invention to such insertion devices, it ispossible to realize precise gap driving and desired magnetic-fieldintensity distributions. Namely, in an insertion device having theaforementioned structure, the first spring supporting frame and thesecond spring supporting frame in the compensation module according tothe present invention are coupled to one and the other one of the firstcoupling beam and the second coupling beam in the insertion devicehaving the aforementioned structure, through the first coupling portionand the second coupling portion, respectively. In this case, the firstspring supporting frame and the second spring supporting frame areallowed to move relative to each other, in the direction in which themagnet arrays are faced to each other. With this structure, momentsinduced by the operations of the compensation spring mechanism can bereceived by the guide mechanism, which inhibits such moments frominfluencing the gap driving mechanism through the first and secondcoupling portions. This can prevent the operations of the compensationspring from influencing the precise gap driving, which can realizeprecise gap driving and a desired magnetic-field intensity distributionin the insertion device having the aforementioned structure.

Further, the compensation module according to the present invention canalso be applied to existing insertion devices having the aforementionedstructure, as well as can be applied as portions of insertion devices tobe newly fabricated. This can improve the gap driving and themagnetic-field intensity distribution in the insertion device.

Preferably, the compensation module according to the present inventioncomprising:

a pair of first plate portions, and a plate coupling portion which isprovided on the first plate portions in their sides farther from themagnet arrays and is adapted to couple the first plate portions to eachother, in a plan view, the first plate portions and the plate couplingportion being provided in one of the first spring supporting frame andthe second spring supporting frame;

a second plate portion placed in such a way as to be sandwiched betweenthe pair of the plate portions in a plan view, the second plate portionbeing provided in the other one of the first spring supporting frame andthe second spring supporting frame; and

the guide mechanism provided between the plate coupling portion and aside of the second plate portion which is farther from the magnetarrays.

Preferably, the compensation module according to the present inventioncomprising:

a pair of first plate portions, and a plate coupling portion which isprovided on the first plate portions in their sides farther from themagnet arrays and is adapted to couple the first plate portions to eachother, in a plan view, the first plate portions and the plate couplingportion being provided in one of the first spring supporting frame andthe second spring supporting frame;

a second plate portion placed in such a way as to be sandwiched betweenthe pair of the plate portions in a plan view, the second plate portionbeing provided in the other one of the first spring supporting frame andthe second spring supporting frame; and

the guide mechanism provided between the sides of the first plateportions which are farther from the magnet arrays, and a side of thesecond plate portion which is farther from the magnet arrays.

Preferably, the compensation module according to the present inventioncomprising:

a first plate portion provided in one of the first spring supportingframe and the second spring supporting frame;

a second plate portion placed in such a way as to be faced to the firstplate portion in a plan view, the second plate portion being provided inthe other one of the first spring supporting frame and the second springsupporting frame; and

the guide mechanism provided between a surface of the first plateportion in its side farther from the magnet arrays and a surface of thesecond plate portion in its side farther from the magnet arrays whichare faced to each other.

With the structures of these compensation modules, moments which thecompensation spring mechanism exerts on the first and second couplingportions can be absorbed by the guide mechanism, which can inhibit themoments induced by the compensation spring from being exerted on thefirst and second coupling portions. This can prevent the operations ofthe compensation spring from influencing the precise gap driving, moreeffectively.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an insertion device according to a firstembodiment, from a front surface side.

FIG. 2 is a perspective view of the insertion device according to thefirst embodiment, from a rear surface side.

FIG. 3 is a front view of the insertion device according to the firstembodiment.

FIG. 4 is a plan view of the insertion device according to the firstembodiment, from above.

FIG. 5A is a side view of the insertion device according to the firstembodiment.

FIG. 5B is a cross-sectional view taken along E-E in FIG. 3.

FIG. 6 is a view taken along an arrow A-A in FIG. 3.

FIG. 7A is a schematic view briefly illustrating the structure of aspring conjunction mechanism and is a perspective view of the same fromthe front surface side.

FIG. 7B is a perspective view illustrating the structure of the springconjunction mechanism from the rear-surface side.

FIG. 7C is a front view of the spring conjunction mechanism.

FIG. 7D is a horizontal cross-sectional view of the center portion ofthe structure of the spring conjunction mechanism.

FIG. 8 is an enlarged perspective view illustrating a compensationmodule.

FIG. 9A is a perspective view of a spring conjunction mechanismaccording to a second embodiment, when viewed from the right side.

FIG. 9B is a perspective view of the spring conjunction mechanismaccording to the second embodiment, when viewed from the left side.

FIG. 9C is a perspective view of the spring conjunction mechanismaccording to the second embodiment, when viewed from the rear surfaceside.

FIG. 9D is a horizontal cross-sectional view of the center portion ofthe spring conjunction mechanism according to the second embodiment.

FIG. 10A is a side view of a compensation module according to the thirdembodiment.

FIG. 10B is a horizontal cross-sectional view of the center portion ofthe spring conjunction mechanism according to the third embodiment.

FIG. 11A is a side view of a compensation module according to a fourthembodiment.

FIG. 11B is a horizontal cross-sectional view of the center portion ofthe spring conjunction mechanism according to the fourth embodiment.

FIG. 12A is a side view of a compensation module according to a fifthembodiment.

FIG. 12B is a horizontal cross-sectional view of the center portion ofthe spring conjunction mechanism according to the fifth embodiment.

MODE FOR CARRYING OUT THE INVENTION

A preferred embodiment (a first embodiment) of an insertion deviceaccording to the present invention will be described, with reference toFIGS. 1 to 6. FIG. 1 is a perspective view of the insertion deviceaccording to the present embodiment, from the front surface side. FIG. 2is a perspective view of the same from the rear surface side. FIG. 3 isa front view of the same. FIG. 4 is a plan view of the same when viewedfrom above. FIG. 5A is a side view of the same when viewed from theright side. FIG. 5B is a cross-sectional view taken along E-E in FIG. 3(wherein a vacuum vessel and peripheral portions therearound are notillustrated). FIG. 6 is a view taken along an arrow A-A in FIG. 3.

As illustrated in FIG. 5A, the insertion device includes a first magnetarray M1 constituted by a plurality of magnets placed in an array, and asecond magnet array M2 constituted by a plurality of magnets placed inan array similarly, which are faced to each other with a gap δinterposed therebetween. An electron beam passes through this gap space.Further, as the magnet arrays, it is possible to employ various types ofexamples of structures, such as ones disclosed in JP-A-2001-143899 andJP-A-2014-13658, as well as one disclosed in Non-Patent Document 1, forexample. Accordingly, the magnet arrays are not limited to particularplacement of magnets.

The first magnet array M1 is supported by a first magnet supportingmember 1, and the second magnet array M2 is supported by a second magnetsupporting member 2. For example, each of the magnets constituting thefirst magnet array M1 is coupled to the first magnet supporting member1, through bolts and the like. The same applies to the second magnetarray M2.

Further, the magnetic arrays, which are the first magnet array M1 andthe second magnet array M2, are faced to each other in the verticaldirection. However, the insertion device is not limited to theaforementioned structure and can also include magnet arrays in ahorizontal direction or in an oblique direction or a combination ofmagnet arrays in two or more directions.

The first magnet array M1 and the second magnet array M2 are installedinside a vacuum vessel 3 which is interiorly maintained at ultra-highvacuum. The vacuum vessel 3 has a circular cylindrical shape, and alsois shaped to be elongated along the leftward and rightward direction inthe figure (the direction of propagation of the electron beam), asillustrated in FIGS. 1 and 3. Further, the gap δ can be changed in sizethrough gap driving mechanisms, which will be described later. A base 10is placed on a placement surface through a plurality of pedestals 4. Anappropriate number of such pedestals 4 can be placed in the front andrear sides.

Further, the vacuum vessel 3 is supported on the base 10 through asupporting body 600. As also illustrated in FIG. 5A, a supporting member610 is provided on the supporting body 600, thereby receiving the lowerportion of the vacuum vessel 3. The supporting body 600, the supportingmember 610 and the vacuum vessel 3 are coupled to each other throughmechanical means (for example, bolts and nuts) which are notillustrated. Further, the supporting body 600 is also coupled to thebase 10 through appropriate mechanical means (for example, bolts andnuts).

Coupling shafts 100 are mounted to an upper portion of the first magnetsupporting member 1, and the coupling shafts 100 are coupled at theirupper ends to coupling plates 101. As illustrated in FIG. 3, eightcoupling shafts 100 are placed along the leftward and rightwarddirection, and eight coupling plates 101 are placed similarly. Asillustrated in FIG. 5A, two coupling shafts 100 are placed along theforward and rearward direction when viewed from the front surface side,and these two coupling shafts 100 are coupled to each other through asingle coupling plate 101. Namely, in the example illustrated in FIGS. 3and 5A, a total of 16 coupling shafts 100 are placed, and the respectivetwo of these 16 coupling shafts 100 are coupled to each other throughthe eight coupling plates 101.

A first coupling beam 103 is placed above the placement of the couplingshafts 100. The first coupling beam 103 and the coupling plates 101 arecoupled to each other, through a magnet supporting member guidemechanism 102 such as a linear guide. This is provided for absorbing thechange of the length of the first magnet supporting member 1, if thefirst magnet supporting member 1 changes in length in the horizontaldirection due to thermal expansion thereof. Accordingly, the gap drivingmechanism and the driving conjunction mechanism are prevented from beinginfluenced by the thermal expansion. As described above, the firstmagnet supporting member 1 and the first coupling beam 103 areintegrally coupled to each other. If the first coupling beam 103 movesin the vertical direction (an example of the direction in which themagnet arrays are faced to each other: the same applies to thefollowing), the first magnet supporting member 1 also moves in thevertical direction integrally therewith, in conjunction with the firstcoupling beam 103. They move in the vertical direction by the sameamount. Further, the mechanism for integrally coupling the firstcoupling beam 103 and the first magnet supporting member 1 to each otheris not limited to the aforementioned structure, and various examples ofmodifications can be applied thereto.

The second magnet supporting member 2 is also integrally coupled to asecond coupling beam 203, through coupling shafts 200, coupling plates201, and a magnet supporting member guide mechanism 202. The structurethereof is the same as that for the first coupling beam 103 and is notdescribed herein. The same applies to the following description.

As illustrated in FIG. 1, the first coupling beam 103 includes amain-body frame 103 a having a rectangular parallelepiped shapeextending along the leftward and rightward direction. Further,supporting frames 103 b are coupled, at two positions, to the rear sideof the main-body frame 103 a and are extended along the forward andrearward direction when viewed from the front surface side.

The Gap Driving Mechanisms

There is provided the gap driving mechanism 50 for changing the size ofthe aforementioned gap δ, in an upper portion of the rear portion of theinsertion device. The gap driving mechanism 50 is installed on the base10 with frames 500 interposed therebetween. As illustrated in FIG. 2,the frames 500 have a rectangular parallelepiped shape with arectangular cross section in the horizontal direction, and there areprovided two such frames 500. A placement plate 501 is provided on theupper portions of the frames 500, and the gap driving mechanism 50 isplaced thereon.

The gap driving mechanism 50 includes a driving motor 51, and conversionportions 52, 53 and 54. The conversion portion 52 converts the drivingtransmission direction by 90 degrees. The conversion portion 53 convertsthe driving transmission direction and transmits the motive power suchthat it diverges leftwardly and rightwardly. There are provided a pairof the conversion portions 54 in the left and right sides which areadapted to convert the driving in the horizontal direction into drivingin the vertical direction. The concrete structure thereof is constitutedby known mechanical elements such as bevel gears.

The conversion portions 54 convert the driving transmission into drivingtransmission in the vertical direction, which drives ball screwmechanisms 7 including a vertical shaft, as illustrated in FIG. 5B, forexample. The ball screw mechanisms 7 are a well-known structure and areconstituted by respective screw shaft portions 70 and respective nutportions 71. The screw shaft portions 70 are supported at their upperand lower sides by bearings 70 a, and the bearings 70 a are mounted tothe frames 500. The nut portions 71 are mounted to the supporting frames103 b. Further, in FIG. 5B, the vacuum vessel 3 and peripheral portionstherearound are not illustrated.

By driving the ball screw mechanisms 7, the screw shaft portions 70 arerotated, thereby moving the nut portions 71 upwardly and downwardly.This can move the first coupling beam 103 in the vertical direction.There are provided the supporting frames 103 b (see FIG. 1), in order tomove the first coupling beam 103 in the vertical direction. When viewedfrom the front surface side, the supporting frames 103 b are mounted attheir rear sides to the front sides of the frames 500 when viewed fromthe front surface side, through two frame guide mechanisms 103 c. Whenviewed from the front surface side, the supporting frames 103 b aremounted, at their front sides, to the first coupling beam 103.

The ball screw mechanisms 7, which are driven by the frame guidemechanisms 103 c and the conversion portions 54 as described above,correspond to a driving conjunction mechanism for coupling the firstcoupling beam 103 and the gap driving mechanism 50 to each other. Bydriving the driving motor 51, the first coupling beam 103 can be movedin the vertical direction, thereby moving the first magnet supportingmember 1 and the first magnet array M1 in the vertical direction.Namely, the size of the gap δ can be changed.

Further, the second coupling beam 203, which is positioned in the lowerside, can also be moved in the vertical direction, similarly, through agap driving mechanism (not illustrated) which is placed in the lowerside. The structure thereof is basically the same as that for the firstcoupling beam 103 and is not described herein. By moving the firstcoupling beam 103 and the second coupling beam 203 in the verticaldirection using the aforementioned structure, it is possible to changethe size of the gap δ. By moving the first coupling beam 103 and thesecond coupling beam 203 in such a direction that they get closer toeach other, the gap δ can be made smaller. By moving them in such adirection that they get farther away from each other, the gap δ can bemade larger.

Compensation Modules

Next, as a preferred embodiment of compensation modules according to thepresent invention, there will be described, at first, a springconjunction mechanism 30, out of compensation spring mechanisms 40 andspring conjunction mechanisms 30 which constitute compensation modules8, with reference to FIGS. 7A, 7B, 7C and 7D. FIG. 7A is a schematicview simply illustrating the structure of the spring conjunctionmechanism 30, which is a perspective view illustrating the same from thefront-surface side. FIG. 7B is a perspective view illustrating the samefrom the rear-surface side. FIG. 7C is a front view of the same. FIG. 7Dis a horizontal cross-sectional view of the center portion in a planview (a top view) (a horizontal cross-sectional view of the centerportion which is provided with a concave portion 310 c in the springconjunction mechanism 30).

The spring conjunction mechanism 30 is constituted by a first springsupporting frame 31, and a second spring supporting frame 32. The firstspring supporting frame 31 includes a pair of first plate portions 310,and the thickwise direction thereof corresponds to the leftward andrightward direction. The first plate portions 310 are installed in sucha way that the plates are erected in the vertical direction. The firstplate portions 310 include an upper-portion protruding portion 310 a, alower-portion protruding portion 310 b, and the concave portion 310 cformed therebetween. As also illustrated in FIG. 5A, the concave portion310 c is shaped to secure a space for placing the vacuum vessel 3therein. In the example of FIGS. 7A to 7C, the lower-portion protrudingportion 310 b is shaped to protrude forwardly (in the side closer to themagnet arrays) more than the upper-portion protruding portion 310 a.However, the upper-portion protruding portion 310 a and thelower-portion protruding portion 310 b can also be shaped to protrude bythe same amount. The lower-portion protruding portions 310 b of the pairof the first plate portions 310 are coupled to each other through acoupling block 33 (see FIGS. 7A and 7B). A portion of the coupling block33 is protruded forwardly more than the lower-portion protrudingportions 310 b, up to the same position as that of an upper-portionprotruding portion 320 a of a second plate portion which will bedescribed later. Further, the coupling block 33 is a preferred example,and the effects of the present invention can also be provided by otherexamples of structures. For example, a portion corresponding to thecoupling block 33 can also be formed integrally with the first plateportions 310.

The pair of the first plate portions 310 are integrally coupled to eachother, at their rear-surface side (their sides farther from the magnetarrays), through a coupling plate 34 (which corresponds to a platecoupling portion).

The second spring supporting frame 32 includes a single second plateportion 320 and is installed in such a way that the plate is erected inthe vertical direction.

The second plate portion 320 is provided in its upper portion with theupper-portion protruding portion 320 a, in its side closer to the magnetarrays. The upper-portion protruding portion 320 a is protrudedforwardly more than the upper-portion protruding portions 310 a. As canalso be seen from FIG. 7C, the second plate portion 320 is placed insuch a way as to be sandwiched between the pair of the first plateportions 310, and they are placed with respective predetermined gapsinterposed therebetween.

A placement plate 35 is placed on the rear side of the second plateportion 320, which is its side farther from the magnet arrays, and aguide mechanism 36 is placed between the placement plate 35 and thecoupling plate 34. Incidentally, in the following description, the guidemechanism 36 will be referred to as a vertical guide mechanism 36, inorder to distinguish it from guide mechanisms installed in otherportions for facilitating understanding. However, it is not intendedthat the guide mechanism 36 should be installed restrictively in thevertical direction (see FIG. 7D). The vertical guide mechanism 36 can beconstituted by a linear guide, for example, such that a guide railtherein is placed on the coupling plate 34, and a guide block therein isplaced on the second plate portion 320. Further, the guide rail and theguide block can also be interchanged in placement. The vertical guidemechanism 36 can also be constituted by other guide mechanisms thanlinear guides. The vertical guide mechanism 36 corresponds to a guidemechanism for guiding the relative movement of the first springsupporting frame 31 and the second spring supporting frame 32 in thevertical direction (in which the magnet arrays are faced to each other).

With this structure, the first spring supporting frame 31 can be movedrelative to the second spring supporting frame 32 in the verticaldirection.

The first plate portions 310 are provided, at their upper end portions,with respective spring placement portions 310 d. Further, the secondplate portion 320 is provided at its upper end portion with acompressive-force exertion portion 320 b. The compressive-force exertionportion 320 b is formed to have a plate shape with a horizontal surface.Compensation springs are placed between the spring placement portions310 d and the compressive-force exertion portion 320 b. Accordingly, thecompressive-force exertion portion 320 b also functions as a springplacement portion. Incidentally, the compensation spring mechanism isnot illustrated in FIG. 7.

FIG. 8 is an enlarged perspective view illustrating a compensationmodule 8. There will be described the compensation spring mechanism 40which constitutes the compensation module 8 together with the springconjunction mechanism 30, with reference to FIG. 8. Spring installationplates 41 are provided on the upper surfaces of the spring placementportions 310 d. A plurality of compensation springs 42 are installed onthe spring installation plates 41. Six compensation springs 42 areplaced in the forward and rearward direction when viewed from the frontsurface side. Incidentally, the number of the compensation springsplaced thereon can be properly determined. As illustrated in the planview of FIG. 4 which illustrates them from above, the compensationmodules 8 (the spring conjunction mechanisms 30 and the compensationspring mechanisms 40) are placed at four positions in the leftward andrightward direction (the direction of propagation of the electron beam).The number of the compensation modules placed therein can be properlydetermined, depending on the length of the insertion device in theleftward and rightward direction. With respect to the compensationspring mechanism 40 at a single position, the compensation springs 42are arranged in two rows (since there is the pair of the first plateportions 310), and there is a total of 12 compensation springs 42.

The compensation springs 42 are constituted by compression coil springs.The compensation springs 42 are placed at their lower end portions onthe spring installation plates 41. Respective pushers 43 are placed onthe upper end portions of the compensation springs 42. The pushers 43are each constituted by a pressing portion 43 a and a bolt portion 43 b,which are integrally formed. The pressing portions 43 a are structuredto press the upper end portions of the compensation springs 42. Thepushers 43 can be fastened to the compressive-force exertion portion 320b, through the bolt portions 43 b. The pushers 43 can be positioned andsecured through nuts 44. The amounts of initial compression of therespective compensation springs 42 can be adjusted, through the pushers43.

Next, there will be described the structure for coupling the springconjunction mechanism 30 to the first and second coupling beams 103 and203. As illustrated in FIG. 6, the upper-portion protruding portion 320a of the second plate portion 320 is coupled, at its tip-end upperportion, to the first coupling beam 103. A coupling plate 104 is mountedto the lower-surface side of the first coupling beam 103, and thecoupling plate 104 is coupled to the second plate portion 320 through acoupling shaft 105. The tip-end upper portion of the upper-portionprotruding portion 320 a, the coupling plate 104 and the coupling shaft105 correspond to a second coupling portion. The second plate portion320 (the second spring supporting frame 32) is allowed to rotate andmove, rather than being completely secured to the first coupling beam103.

The lower-portion protruding portions 310 b of the first plate portions310 are coupled, at their tip-end lower portions, to the second couplingbeam 203, through the coupling block 33. A coupling plate 204 is mountedto the upper-surface side of the second coupling beam 203, and thecoupling plate 204 is coupled to the first plate portions 310 through acoupling shaft 205. The tip-end lower portions of the lower-portionprotruding portions 310 b, the coupling block 33, the coupling plate 204and the coupling shaft 205 correspond to a first coupling portion. Thefirst plate portions 310 (the first spring supporting frame 31) areallowed to rotate and move, rather than being completely secured to thesecond coupling beam 203. As described above, the compensation springmechanisms 40 and the first magnet supporting member 1 and the secondmagnet supporting member 2 are coupled to each other through the springconjunction mechanisms 30, with various members such as the couplingbeams 103 and 203 interposed therebetween. Further, in FIGS. 1 to 6 and8, the compensation modules 8 are all installed in the rear side withrespect to the magnet arrays (in the side closer to the frames 500 withrespect to the vacuum vessel 3). However, the compensation modules 8 canalso be installed in the front side (in the opposite side from theframes 500 with respect to the vacuum vessel 3) or can be installed inthe opposite sides across the vacuum vessel 3, depending on thestructure of the insertion device in which the compensation modules areinstalled and depending on the required sizes of the spring forces.

Gap Changing Operations

There will be described operations for changing the gap δ, withreference to FIGS. 6 and 8. Through the gap driving mechanisms 50, thefirst coupling beam 103 is moved downwardly, and the second couplingbeam 203 is moved upwardly. Thus, the first magnet supporting member 1and the first magnet array M1 are moved downwardly, and the secondmagnet supporting member 2 and the second magnet array M2 are movedupwardly. Consequently, the first magnet array M1 and the second magnetarray M2 get closer to each other, thereby making the gap δ smaller. Atthe same time, the attractive force between the magnets is made larger.

Further, the second plate portion 320 is moved downwardly since thefirst coupling beam 103 is moved downwardly. Further, the first plateportions 310 are moved upwardly since the second coupling beam 203 ismoved upwardly. As a result thereof, the compensation springs 42 in thecompensation spring mechanisms 40 are compressed. As the gap δ is madesmaller, the attractive force from the magnets is made larger and, inconjunction therewith, the spring forces in the compensation springmechanisms 40 are made larger. If the attractive force is made larger,this exerts forces which attempt to deform the coupling beams, which areintegrally coupled to the magnet supporting bodies supporting the magnetarrays. If the coupling beams are deformed, the magnet supporting bodiesare also deformed, which makes the size of the gap δ non-constant in therightward and leftward direction, which is the direction of the electronbeam, thereby making it impossible to maintain the magnetic-fieldintensity distribution in the direction of the electron beam which hasbeen initially set. For coping therewith, the compensation springmechanisms 40 are provided, in order to suppress the deformations of thecoupling beams due to attractive forces.

Along with the increase of the compressive forces of the compensationsprings 42, respective moments in opposite directions may be exerted onthe first coupling portion and the second coupling portion. These bothmoments are cancelled by the portion of the vertical guide mechanism 36.This prevents so large moments from being exerted on the first andsecond coupling portions. Further, in the present embodiment, the firstand second coupling portions are constituted by coupling structuresincluding a shaft and a fitting hole. Therefore, even if a residualmoment is exerted thereon due to cancelling errors, the moment can beabsorbed by slight relative rotation of the shaft and the fitting hole.This can inhibit moments induced by the compensation spring mechanisms40 from adversely influencing the gap driving mechanisms 50, therebypreventing the accurate gap driving from being influenced thereby.

Further, in the present embodiment, the first and second couplingportions are provided on the upper end portion of the second couplingbeam 203 and on the lower end portion of the first coupling beam 103,respectively. Namely, both of the first and second coupling portions areprovided in the side closer to the magnet arrays. This can inhibit theincrease of the sizes of the first spring supporting frame 31 and thesecond spring supporting frame 32 in the upward and downward direction.Further, the compensation spring mechanisms 40 are provided in the rearside with respect to the vacuum vessel 3 when viewed from the frontsurface side. When viewed from the front-surface side, the front sidewith respect to the vacuum vessel 3 is opened. This prevents thecompensation spring mechanisms 40 from obstructing works whichnecessitate accessing the vacuum vessel 3 and the magnet arrays from thefront side when viewed from the front surface side.

Further, regarding the respective elements constituting the springconjunction mechanisms 30, it is possible to properly determine thematerials thereof, the methods for fabricating them, and theconstitutions of members therein, such as whether the respectiveelements are constituted by a single member or by a combination ofplural members, for example. Further, the same applies to the structuresof the plate portions, and the shapes thereof are not limited tocomplete plates (flat plates).

Second Embodiment

Next, there will be described a second embodiment of the springconjunction mechanisms 30, with reference to FIGS. 9A, 9B, 9C and 9D.FIG. 9A is a perspective view illustrating a spring conjunctionmechanism according to the second embodiment, when viewed from the frontsurface side, from the right side and from above. FIG. 9B is aperspective view of the same when viewed from the front-surface side,from the left side and from above. FIG. 9C is a perspective view of thesame when viewed from the rear surface side. FIG. 9D is a horizontalcross-sectional view of the center portion in a plan view (a top view)(a horizontal cross-sectional view of the center portion which isprovided with a concave portion 310 c in the spring conjunctionmechanism 30). Further, in the following embodiments, the elementshaving the same functions as those of the first embodiment may bedesignated by the same reference characters as those of the firstembodiment and will not be described in some cases.

In the present embodiment, a first spring supporting frame 31 isconstituted by a single first plate portion 310. A second springsupporting frame 32 is constituted by a second plate portion 320, whichis faced to the first plate portion 310 with a predetermined intervalinterposed therebetween. A vertical guide mechanism 36 is providedbetween their surfaces faced to each other. The vertical guide mechanism36 is placed at a position in the side farther from magnet arrays.Similarly to the first embodiment, there are provided a spring placementportion 310 d and a compressive-force exertion portion 320 b, andcompensation spring mechanisms 40 (not illustrated) are placedtherebetween. The tip-end upper portion of an upper-portion protrudingportion 320 a provided in the side closer to the magnet arrays, acoupling plate 104 and a coupling shaft 105 correspond to a secondcoupling portion. The tip-end lower portion of a lower-portionprotruding portion 310 b provided in the side closer to the magnetarrays, a coupling plate 204 and a coupling shaft 205 correspond to afirst coupling portion.

In the second embodiment, the plate portions have a two-layerconfiguration and have a simplified structure, which can also contributeto weight reduction.

Third Embodiment

Next, there will be described a third embodiment of the springconjunction mechanisms 30, with reference to FIGS. 10A and 10B. FIG. 10Ais a side view of a spring conjunction mechanism 30 according to thethird embodiment. FIG. 10B is a horizontal cross-sectional view (a viewtaken along an arrow B-B) of the center portion in a plan view (a topview). In the third embodiment, the plate portions have a three-layerconfiguration, similarly to the first embodiment. Vertical guidemechanisms 36 are different in placement from that in the firstembodiment. As illustrated in FIG. 10B, the vertical guide mechanisms 36are placed between the surfaces of first plate portions 310 and a secondplate portion 320 which are faced to each other, in the side fartherfrom magnet arrays.

Fourth Embodiment

Next, there will be described a fourth embodiment of the springconjunction mechanisms 30, with reference to FIGS. 11A and 11B. FIG. 11Ais a side view of a spring conjunction mechanism 30 according to thefourth embodiment. FIG. 11B is a horizontal cross-sectional view (a viewtaken along an arrow C-C) of the center portion in a plan view (a topview).

In the present embodiment, there is provided a fixed frame 60, which issecured to a base 10 (or a placement surface such as a floor, whichcorresponds to a foundation) with a supporting frame 61 interposedtherebetween. The fixed frame 60 is formed to have a plate shape and isadapted not to move, regardless of the operations of compensationsprings 42. Second plate portions 320 are placed in an upper side in thevertical direction, and first plate portions 310 are placed in a lowerside. A pair of the first plate portions 310 and a pair of the secondplate portions 320 are placed in such a way as to sandwich the fixedframe 60 therebetween. There are provided respective vertical guidemechanisms 36, between the surfaces of the first plate portions 310 andthe fixed frame 60 which are faced to each other, and between thesurfaces of the second plate portions 320 and the fixed frame 60 whichare faced to each other. They function as a first vertical guidemechanism and a second vertical guide mechanism, respectively.

The first plate portions 310 include a protruding portion 310 e in thefront side which is the side closer to the magnet arrays, and the secondplate portions 320 include a protruding portion 320 e in the front sidewhich is the side closer to the magnet arrays. The first and secondcoupling portions have the same structure. Compensation springmechanisms 40 are placed between the first plate portions 310 and thesecond plate portions 320.

The spring conjunction mechanisms 30 can be maintained at a stabilizedstate, since they are secured to the placement surface through the fixedframe 60.

Fifth Embodiment

Next, there will be described a fifth embodiment of the springconjunction mechanisms 30. FIG. 12A is a side view of a springconjunction mechanism 30 according to the fifth embodiment. FIG. 12B isa horizontal cross-sectional view (a view taken along an arrow D-D) ofthe center portion in a plan view (a top view).

In the fifth embodiment, there are provided a pair of fixed frames 62,which are coupled to each other through a coupling plate 63 at theirrear sides, which are their sides farther from magnet arrays. Further,the coupling plate 63 is further secured to a base 10 (or a placementsurface such as a floor, which corresponds to a foundation), through asupporting frame 61. Between the pair of the fixed frames 62 faced toeach other, a second plate portion 320 is provided in an upper-portionspace, and a first plate portion 310 is provided in a lower-portionspace. The first plate portion 310 is provided with a protruding portion310 e in its side closer to the magnet arrays, and the second plateportion 320 is provided with a protruding portion 320 e in its sidecloser to the magnet arrays.

There are provided respective compensation spring mechanisms 40 on thelower side of the first plate portion 310 and on the upper side of thesecond plate portion 320. A placement plate 35 is provided on the rearside of the first plate portion 310 which is its side farther from themagnet arrays, and a vertical guide mechanism 36 (corresponding to afirst vertical guide mechanism) is provided between the placement plate35 and the coupling plate 63. A placement plate 35 is also provided onthe rear side of the second plate portion 320 which is its side fartherfrom the magnet arrays, similarly, and a vertical guide mechanism 36(corresponding to a second vertical guide mechanism) is provided betweenthe placement plate 35 and the coupling plate 63. The first and secondcoupling portions have the same structure.

Other Embodiments

It is possible to conceive various types of examples of modificationsregarding the concrete structure of the gap driving mechanisms, and thestructure of the gap driving mechanisms is not limited to the structureaccording to the present embodiment. In the present embodiment, thefirst coupling beam 103 and the second coupling beam 203 in the upperand lower sides are both adapted to move in the vertical direction.However, only any one of them can be adapted to move. The gap drivingmechanisms can be either provided both above and under the vacuum vessel(the magnet arrays) or provided only thereabove or thereunder.

In the present embodiment, compressive coil springs are employed as thecompensation springs 42. However, the compensation springs 42 are notlimited thereto. Further, it is also possible to employ hydrauliccylinders (a type of liquid springs) or compressed-air cylinders (a typeof gas springs), which are springs in a broad sense. In this case, thespring stresses can be controlled by adjusting the hydraulic pressure orthe air pressure.

In the present embodiment, the compensation spring mechanisms are placedonly above the magnet arrays. However, the compensation springmechanisms can also be placed only under the magnet arrays or both aboveand under the magnet arrays.

In the present embodiment, the first coupling portion and the secondcoupling portion are adapted to attain coupling in such a way as toallow relative rotation therein. However, the first coupling portion andthe second coupling portion can also have a coupling configurationadapted to prevent relative rotation therein.

Further, as such a structure for allowing relative rotation therein, itis also possible to employ other structures than that in the presentembodiment. Regarding the relationship between the fitting holes and theshafts in the first and second coupling portions, the shafts can beintegrally provided in any of the coupling-beam side and thespring-conjunction-mechanism side, and the fitting holes can be providedin the other. Also, the fitting holes can be provided in both of them,while the shafts can be formed to be independent members. Further in thecase of providing the fitting holes in the spring-conjunction-mechanismside, the fitting holes are designated by reference characters 310 f,320 f and 33 a (FIG. 7A and the like).

In the present embodiment, the second spring supporting frame 32 iscoupled to the first coupling beam 103, and the first coupling beam 103is coupled to the second coupling beam 203. However, they can also beinterchanged.

In the present embodiment, the terms “first” and “second” are used forvarious types of components, and they are used for convenience of thedescription. These terms are not intended to restrict the placements ofelements, for example, such that they should be positioned at upper orlower positions.

In the present embodiment, the first coupling portion and the secondcoupling portion are provided on the lower end portion of the firstcoupling beam 103 and on the upper end portion of the second couplingbeam 203, in order that they can get closest to the magnet arrays.However, the first coupling portion and the second coupling portion arenot limited thereto. Any one of the first and second coupling portionscan also be provided on the upper end portion of the first coupling beam103 or can be provided at a position at the height of the centerportion. The same applies to the second coupling beam 203.

The insertion device to which the characteristic structures such as thecompensation modules and the like according to the present invention areapplied is not limited to that described in the present embodiment.These characteristic structures can also be applied to various types ofinsertion devices which have been conventionally well known. Further,the compensation modules according to the present invention can also beapplied to existing insertion devices having the same structure, as wellas can be applied as portions of insertion devices to be newlyfabricated.

DESCRIPTION OF REFERENCE SIGNS

-   M1 First magnet array-   M2 Second magnet array δ Gap-   1 First magnet supporting member-   2 Second magnet supporting member-   3 Vacuum vessel-   4 Pedestal-   10 Base-   100 Coupling shaft (magnet supporting member coupling shaft)-   101 Coupling plate (magnet supporting member coupling plate)-   102 Magnet supporting member guide mechanism-   103 First coupling beam-   104 Coupling plate (beam coupling plate)-   105 Coupling shaft (beam coupling shaft)-   200 Coupling shaft (magnet supporting member coupling shaft)-   201 Coupling plate (magnet supporting member coupling plate)-   202 Magnet supporting member guide mechanism-   203 Second coupling beam-   204 Coupling plate (beam coupling plate)-   205 Coupling shaft (beam coupling shaft)-   30 Spring conjunction mechanism-   31 First spring supporting frame-   32 Second spring supporting frame-   33 Coupling block-   33 a Fitting hole-   34 Coupling plate-   36 Guide mechanism (vertical guide mechanism)-   310 First plate portion-   310 a Upper-portion protruding portion-   310 b Lower-portion protruding portion-   310 d Spring placement portion-   310 e Protruding portion-   310 f Fitting hole-   320 Second plate portion-   320 a Upper-portion protruding portion-   320 b Compressive-force exertion portion-   320 e Protruding portion-   320 f Fitting hole-   40 Compensation spring mechanism-   42 Compensation spring-   43 Pusher-   43 a Pressing portion-   50 Gap driving mechanism-   60 Fixed frame-   61 Supporting frame-   62 Fixed frame-   7 Ball screw mechanism-   70 Screw shaft portion-   71 Nut portion-   8 Compensation module

1. An insertion device comprising: a first magnet array comprising aplurality of magnets placed in an array; a first magnet supportingmember adapted to support the first magnet array mounted to the firstmagnet supporting member; a second magnet array comprising a pluralityof magnets placed in an array and being faced to the first magnet arraywith a gap interposed therebetween; a second magnet supporting memberadapted to support the second magnet array mounted to the second magnetsupporting member; a gap driving mechanism for driving the first magnetsupporting member and/or the second magnet supporting member in adirection in which the magnet arrays are faced to each other, in orderto change a size of the gap; a first coupling beam coupled integrally tothe first magnet supporting member; a second coupling beam coupledintegrally to the second magnet supporting member; a driving conjunctionmechanism for coupling at least one of the first coupling beam and thesecond coupling beam to the gap driving mechanism; a compensation springmechanism adapted to act in such a direction as to cancel an attractiveforce acting between the first magnet array and the second magnet array;and a spring conjunction mechanism for coupling the compensation springmechanism and the coupling beams to each other, wherein the springconjunction mechanism includes: a first spring supporting frame coupled,through a first coupling portion, to one of the first coupling beam andthe second coupling beam, a second spring supporting frame coupled,through a second coupling portion, to the other one of the firstcoupling beam and the second coupling beam, and a guide mechanism forguiding relative movement of the first spring supporting frame and thesecond spring supporting frame, in the direction in which the magnetarrays are faced to each other, the compensation spring mechanism ismounted to both the first spring supporting frame and the second springsupporting frame and, when the size of the gap is changed, the firstspring supporting frame and the second spring supporting frame moverelative to each other in the direction in which the magnet arrays arefaced to each other, so that the compensation spring mechanism operates.2. The insertion device according to claim 1, wherein one of the firstspring supporting frame and the second spring supporting frame includesa pair of first plate portions, and a plate coupling portion which isprovided on the first plate portions in their sides farther from themagnet arrays and is adapted to couple the first plate portions to eachother, in a plan view, the first plate portions are coupled, at theirsides closer to the magnet arrays, to one of the first coupling beam andthe second coupling beam, through the first coupling portion, the otherone of the first spring supporting frame and the second springsupporting frame includes a second plate portion placed in such a way asto be sandwiched between the pair of the plate portions in a plan view,the second plate portion is coupled, at its side closer to the magnetarrays, to the other one of the first coupling beam and the secondcoupling beam, through the second coupling portion, and the guidemechanism is provided between the plate coupling portion and a side ofthe second plate portion which is farther from the magnet arrays.
 3. Theinsertion device according to claim 1, wherein one of the first springsupporting frame and the second spring supporting frame includes a pairof first plate portions, and a plate coupling portion which is providedon the first plate portions in their sides farther from the magnetarrays and is adapted to couple the first plate portions to each other,in a plan view, the first plate portions are coupled, at their sidescloser to the magnet arrays, to one of the first coupling beam and thesecond coupling beam, through the first coupling portion, the other oneof the first spring supporting frame and the second spring supportingframe includes a second plate portion placed in such a way as to besandwiched between the pair of the plate portions in a plan view, thesecond plate portion is coupled, at its side closer to the magnetarrays, to the other one of the first coupling beam and the secondcoupling beam, through the second coupling portion, and the guidemechanism is provided between the sides of the first plate portionswhich are farther from the magnet arrays, and a side of the second plateportion which is farther from the magnet arrays.
 4. The insertion deviceaccording to claim 1, wherein one of the first spring supporting frameand the second spring supporting frame includes a first plate portion ina plan view, the first plate portions is coupled, at its side closer tothe magnet arrays, to one of the first coupling beam and the secondcoupling beam, through the first coupling portion, the other one of thefirst spring supporting frame and the second spring supporting frameincludes a second plate portion placed in such a way as to be faced tothe first plate portion in a plan view, the second plate portion iscoupled, at its side closer to the magnet arrays, to the other one ofthe first coupling beam and the second coupling beam, through the secondcoupling portion, and the guide mechanism is provided between a surfaceof the first plate portion in its side farther from the magnet arraysand a surface of the second plate portion in its side farther from themagnet arrays which are faced to each other.
 5. The insertion deviceaccording to claim 1, wherein the first coupling portion and the secondcoupling portion have a structure for coupling through a combination ofa shaft and a fitting hole fittable to the shaft.
 6. The insertiondevice according to claim 1, wherein one of the first spring supportingframe and the second spring supporting frame is provided with aplacement portion adapted to place, thereon, a compensation spring inthe compensation spring mechanism, and the other one of the first springsupporting frame and the second spring supporting frame is provided witha compressive-force exertion portion adapted to exert a compressiveforce on the compensation spring.
 7. The insertion device according toclaim 1, wherein the spring conjunction mechanism further comprises afixed frame secured to a foundation, and a plurality of the guidemechanisms, and the spring conjunction mechanism comprises: a firstguide mechanism adapted to guide the first spring supporting framerelative to the fixed frame in the direction in which the magnet arraysare faced to each other, and a second guide mechanism adapted to guidethe second spring supporting frame relative to the fixed frame in thedirection in which the magnet arrays are faced to each other, and whenthe size of the gap is changed, the spring conjunction mechanism isadapted to allow the first spring supporting frame and the second springsupporting frame to move relative to the fixed frame, in the directionin which the magnet arrays are faced to each other.
 8. The insertiondevice according to claim 1, wherein the second coupling portion isprovided on the first coupling beam in its side closer to the firstmagnet array, and the first coupling portion is provided on the secondcoupling beam in its side closer to the second magnet array.
 9. Theinsertion device according to claim 1, wherein the spring conjunctionmechanism is placed in a rear side with respect to the magnet arrays, ina side view.
 10. A compensation module for use in an insertion device,the insertion device comprising: a first magnet array comprising aplurality of magnets placed in an array; a first magnet supportingmember adapted to support the first magnet array mounted to the firstmagnet supporting member; a second magnet array comprising a pluralityof magnets placed in an array and being faced to the first magnet arraywith a gap interposed therebetween; a second magnet supporting memberadapted to support the second magnet array mounted to the second magnetsupporting member; a gap driving mechanism for driving the first magnetsupporting member and/or the second magnet supporting member in adirection in which the magnet arrays are faced to each other, in orderto change a size of the gap; a first coupling beam coupled integrally tothe first magnet supporting member; a second coupling beam coupledintegrally to the second magnet supporting member; and a drivingconjunction mechanism for coupling at least one of the first couplingbeam and the second coupling beam to the gap driving mechanism, thecompensation module comprising: a compensation spring mechanism adaptedto act in such a direction as to cancel an attractive force actingbetween the first magnet array and the second magnet array; and a springconjunction mechanism for coupling the compensation spring mechanism andthe coupling beams to each other, wherein the spring conjunctionmechanism includes: a first spring supporting frame coupled, through afirst coupling portion, to one of the first coupling beam and the secondcoupling beam, a second spring supporting frame coupled, through asecond coupling portion, to the other one of the first coupling beam andthe second coupling beam, and a guide mechanism for guiding relativemovement of the first spring supporting frame and the second springsupporting frame, in the direction in which the magnet arrays are facedto each other, and the compensation spring mechanism is mounted to boththe first spring supporting frame and the second spring supporting frameand, when the size of the gap is changed, the first spring supportingframe and the second spring supporting frame move relative to each otherin the direction in which the magnet arrays are faced to each other, sothat the compensation spring mechanism operates.
 11. The compensationmodule according to claim 10, comprising: a pair of first plateportions, and a plate coupling portion which is provided on the firstplate portions in their sides farther from the magnet arrays and isadapted to couple the first plate portions to each other, in a planview, the first plate portions and the plate coupling portion beingprovided in one of the first spring supporting frame and the secondspring supporting frame; a second plate portion placed in such a way asto be sandwiched between the pair of the plate portions in a plan view,the second plate portion being provided in the other one of the firstspring supporting frame and the second spring supporting frame; and theguide mechanism provided between the plate coupling portion and a sideof the second plate portion which is farther from the magnet arrays. 12.The compensation module according to claim 10, comprising: a pair offirst plate portions, and a plate coupling portion which is provided onthe first plate portions in their sides farther from the magnet arraysand is adapted to couple the first plate portions to each other, in aplan view, the first plate portions and the plate coupling portion beingprovided in one of the first spring supporting frame and the secondspring supporting frame; a second plate portion placed in such a way asto be sandwiched between the pair of the plate portions in a plan view,the second plate portion being provided in the other one of the firstspring supporting frame and the second spring supporting frame; and theguide mechanism provided between the sides of the first plate portionswhich are farther from the magnet arrays, and a side of the second plateportion which is farther from the magnet arrays.
 13. The compensationmodule according to claim 10, comprising: a first plate portion providedin one of the first spring supporting frame and the second springsupporting frame; a second plate portion placed in such a way as to befaced to the first plate portion in a plan view, the second plateportion being provided in the other one of the first spring supportingframe and the second spring supporting frame; and the guide mechanismprovided between a surface of the first plate portion in its sidefarther from the magnet arrays and a surface of the second plate portionin its side farther from the magnet arrays which are faced to eachother.